diff --git a/sql/item.h b/sql/item.h
index 22eb0c08e2d..31d501dc5c3 100644
--- a/sql/item.h
+++ b/sql/item.h
@@ -470,6 +470,13 @@ public:
   my_string name;			/* Name from select */
   /* Original item name (if it was renamed)*/
   my_string orig_name;
+  /**
+     Intrusive list pointer for free list. If not null, points to the next
+     Item on some Query_arena's free list. For instance, stored procedures
+     have their own Query_arena's.
+     
+     @see Query_arena::free_list
+  */
   Item *next;
   uint32 max_length;
   uint name_length;                     /* Length of name */
diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc
index 807d6c09a46..d0a4fff442f 100644
--- a/sql/sql_parse.cc
+++ b/sql/sql_parse.cc
@@ -1411,8 +1411,10 @@ end:
 }
 
 
-    /* This works because items are allocated with sql_alloc() */
-
+/**
+   This works because items are allocated with sql_alloc().
+   @note The function also handles null pointers (empty list).
+*/
 void cleanup_items(Item *item)
 {
   DBUG_ENTER("cleanup_items");  
diff --git a/sql/sql_update.cc b/sql/sql_update.cc
index 35ae0febcec..8d666c771ec 100644
--- a/sql/sql_update.cc
+++ b/sql/sql_update.cc
@@ -908,8 +908,9 @@ reopen_tables:
       items from 'fields' list, so the cleanup above is necessary to.
     */
     cleanup_items(thd->free_list);
-
+    cleanup_items(thd->stmt_arena->free_list);
     close_tables_for_reopen(thd, &table_list);
+
     goto reopen_tables;
   }